The steering column of a motor vehicle takes on the bearing of the upper steering train, consisting of a single- or multi-part shaft with interfaces toward the steering wheel and toward the intermediate steering shaft. The intermediate steering shaft is coupled onto the steering column and produces the connection to the steering gear. Furthermore, the steering column makes it possible to position the steering wheel in relation to the driver.
DE 10 2005 034 952 B3 discloses, for example, a steering column, the height and the inclination of which are adjustable. A steering spindle is mounted rotatably in a setting part, which is also called sleeve unit, steering-column tube or steering spindle mounting unit. The sleeve unit is held in a holding part and the holding part is mounted in a holding clamp, which can be fastened to a vehicle body. In order to adapt the position of the steering spindle, or of a steering wheel to be fastened thereto, a clamping system is provided which is adjustable between an open position and a closed position with a setting lever. In the open position of the clamping system, the sleeve unit can be displaced in the longitudinal direction thereof with respect to the holding part and at the same time the holding part can be pivoted in the inclination thereof about a pivot axis in relation to the holding clamp. In the closed position of the clamping system, the steering spindle is fixed in relation to the holding clamp mounted on the body. Steering columns and clamping systems of this type are known in various embodiments in the prior art.
Furthermore, the steering column makes a considerable contribution to driving safety. In the event of an accident, the steering column yields in a defined manner when the driver impacts against the airbag.
In the technical configuration of the steering column, there is a conflict of objectives in terms of requirements for installation space, rigidity and weight. Steering columns of the type in question and the components thereof are presently preferably made from steel, sheet metal, and cast aluminum or magnesium.
However, it is desirable to reduce the weight of the steering column and the structural elements thereof while the strength and rigidity properties remain at least the same. This reduction would lead to a favorable effect on fuel consumption and to improving the driving dynamics of motor vehicles and to increasing the range of electric vehicles.
A minimization of the dead weight while keeping rigidity and strength the same can be achieved by the use of specific materials, such as, for example, fiber composite materials.
Fiber-composite materials are composed of reinforced fibers which are embedded in a matrix. The general rule is that the specific rigidity of a fiber-composite material or of a hybrid material from metal and a fiber-composite material is higher than that of metal alone. The superior properties are only achieved by way of the interaction of both components. A multiplicity of manufacturing methods, in which the fibers which have been preimpregnated with a matrix material are processed, exist. One of the established manufacturing methods is the method of fiber winding. In the fiber-winding method the endless fiber strands (rovings) are wound onto a winding core in a continuous process. The fibers here are often soaked and wet-impregnated with a matrix resin during the same operational step, or non-soaked fibers which are soaked after the winding process by way of a resin-injection method are processed. The fiber-winding process is distinguished by high laminate quality and high precision in terms of the fiber-resin content and in terms of fiber orientation, while at the same time having a high degree of automation and being very economical.
A lattice-type component from a fiber-reinforced plastics material, and a method for manufacturing the same are disclosed in EP 1 268 164 B1. Manufacturing of the lattice-type component is performed by the fiber-winding method, depending on the predetermined stress or the stress to be expected. To this end, a number of winding spools around which the preimpregnated fibers are wound are provided on a winding plate. The cavities between the thus created external belt parts and the intermediate structure are, at least in regions, filled with a filler material. The filler material supports those portions of the lattice-type intermediate structure that are compression-loaded and prevents uncontrolled buckling when the calculated load of said portions is exceeded. Lattice-type structures are distinguished by their high level of stability. It is envisaged that these elements are employed as support beams, for example in a vehicle chassis, the filler material inter alia facilitating the absorption of energy in the event of a crash. The shape and the profile of the reinforcement of the support-beam component cannot be individually designed on account of the predetermined lattice-type structure. The reinforcement may indeed be adapted to the load by way of a variable number of fibers, but a specific design embodiment along force lines of a component is not possible.